Heavy metals pollution and the identification of their sources in soil over Xiaoqinling gold-mining region,Shaanxi, China |
| |
| Authors: | Yaoguo Wu Youning Xu Jianghua Zhang Sihai Hu Kai Liu |
| |
| Institution: | (1) Department of Applied Chemistry, Northwestern Polytechnical University, Xi’an, 710072, China;(2) Xi’an Institutes of Geology and Mineral Resources, Xi’an, 710054, China |
| |
| Abstract: | In order to determine the characteristics of heavy metals’ pollution and identify their sources in the soil over the Xiaoqinling
gold-mining region, Shaanxi, China, 133 soil samples were collected over the region, one sample was from a close point as
background, and concentrations of Hg, Pb, Cu, and As in all samples were analyzed. Results indicated that the soil was polluted
by these heavy metals, as their concentrations in the soil over the studied region were higher than that in the background
zone. In addition, the result indicated that these metals had their specific spatial characteristics. Among the samples, those
with higher concentrations of Hg, Pb, and Cu were mainly collected from the Shuangqiao river alluvial terrace area, the loess
ravine tableland, and the piedmont alluvial–pluvial inclined tableland, which are the areas of gold-mining activities. Meanwhile,
the samples with higher concentrations of As were distributed over the loess ravine tableland around Tongguan County, where
agricultural activities were conducted intensively. Furthermore, the sources for all the heavy metals Hg, Pb, Cu, and As in
the soil over each landscape were determined through analyzing the concentration correlation of these metals and comparing
the maps of metal concentration distribution and land-use types. In Yellow river–Weihe river alluvial plain area, these heavy
metals were mainly from agricultural activities. In the other landscapes, As was also mainly from agricultural activities;
the other metals were contrarily from the gold-related activities. Interestingly, the correlation coefficients of As concentrations
with Hg, Pb or Cu concentrations were positive in the samples from Yellow river–Weihe river alluvial plain area, and on the
contrary, they were negative in the samples from the other landscapes. This result showed that the correlation can be used
as an index to indicate properly the effect of the gold-related or agricultural activities on the heavy metals in the soil
and identify their main sources over each landscape. As human activities resulted in the site-specific characteristics in
the concentrations and sources of the heavy metals in each landscape, site-specific control strategies should be selected
intensively to remedy landscape soil pollution. In Yellow river–Weihe river plain area, effective control strategies should
be aimed at remedying As pollution caused by agricultural activities; in the other landscapes, Hg, Pb and Cu pollution caused
by gold-mining activities should be considered. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
